Method of and apparatus for drying



March 28, 1950 H. A. KULJIAN METHOD OF AND APPARATUSFOR DRYING 2 Sheets-Sheet 1 Filed July 17, 1947 i y V7. W m n fi W M4 March 28, 1950 H. A. KULJIAN METHOD OF AND APPARATUS FOR DRYING 2 Sheets-Sheet 2 Filed July 17, 1947 INKENTOR. f/dF/y A 11/ 1:272

36m 77m Attorny Patented Mar. 28, 1950 UNITED STATES PATENT OFFICE METHOD OF AND APPARATUS FOR DRYING Harry Asdour Kuljian, Merion, Pa.

Application July 17, 1947, Serial No. 761,509

Claims. (Cl. 219-47) My invention relates to a drying apparatus of the type which employs the heating effect which results when a material having a considerable dielectric loss characteristic is placed in a highfrequency electric field.

One object of the invention is to produce an improved apparatus for, and an improved method of, drying or otherwise treating a dielectric material by the use of dielectric heating.

A further object of the invention is to produce an improved apparatus for, and an improved method of, drying or otherwise treating natural or synthetic yarns, textiles or other materials having relatively high dielectric loss characteristics.

A still further object of the invention is to produce an improved apparatus for, and an improved method of, drying or otherwise treating dielectric materials, whereby the material to be dried or treated is fully exposed to the action of a controlled high-frequency electric field and whereby the means which support the material is substantially wholly excluded from the high-frequency field, thereby assuring adequate heating of the material and insuring against heating of the supporting means by the action of the high frequency electric field.

A still further object of the invention is to produce an improved apparatusv for, and an improved method of, drying or otherwise treating yarn, whereby a controlled portion or portions of the yarn may, simultaneously or successively, be subjected. for controlled periods of time, to constant or variable, but controlled, action of a high-frequency electric field.

A still further object is to produce an improved apparatus for, and an improved method of, drying or otherwise treating a yarn, with the yarn moving, single-file, through a high-frequency electric field, as distinguished from subjecting a spool or cake of yarn to the action of a high-frequency electric field.

A still further object of the invention is to produce an improved apparatus for, and an improved method of, drying or otherwise treating yarn. whereby the principle of dielectric heating is employed in conjunction with a thread storing and advancing device of the type which includes two or more spaced olls, the axis of at least one of which is skewed, and at least one of which rolls is rotated about its axis, whereby the device causes a yarn wound thereabout to move, in the form of a helix having a plurality of spaced convolutions, axially of the device.

A still further object of this invention is to produce an improved apparatus which can be used for drying only or for subjecting the material to heat while such material is being liquidtreated, set or cured.

These and other objects are effected by the invention as set forth in the following specification and as illustrated in the accompanying drawings in which:

Fig. 1 is a fragmentary and diagrammatic view in side elevation showing the application of my invention to the drying of a synthetic thread.

Fig. 2 is a fragmentary end elevational view looking in the direction or line 22 on Fig. 1.

Fig. 3 is a fragmentary vertical sectional view taken on line 33 on Fig. 1.

Fig. 4 is a view, similar to Fig. 1, showing another application of the invention.

In the particular application illustrated in the drawings, there is shown, in a highly diagrammatic manner, an apparatus for continuous manufacture of synthetic yarn, which apparatus includes a spinnerette 10 which extrudes an appropriate solution into a coagulating bath 12 to form a filament M. The filament l4 passes over suitable stretching and guiding devices 15, and. onto a thread-storing and advancing device which is adapted to receive and advance the thread, in the form of a helix having a plurality of spaced convolutions l6, from one end of said device to the other.

The thread-storing and advancing device, as such, does not form part of the present invention and is, therefore, not shown or described in detail. It is sufficient to state that the threadstoring and advancing device is formed of a plurality of spaced rotary rolls H, with the axis of one or more of the rolls skewed with respect to the axis of a central, fixed roll l8, and with one or more of the rolls rotated about its individual axis. By this structure, a thread wound about one end of said device, will travel, axially of the device, in the form of a helix having more or less closely spaced convolutions it until it reaches and leaves the other end of the device. One or more of the rolls may be rotated by a suitable gear arrangement l9 driven by a motor M, and the entire thread-storing and advancing device is mounted, in cantilever fashion, on a frame 20. The ends of the rolls ll are provided with ball bearings 2|, and the axis of one or more of the rolls may be skewed, by rotation of a handle 22 which is arranged to move the left-hand ends of the rolls, as viewed in Fig. 1, to cause the thread to move longitudinally of the rolls as above set forth. It will be understood that the spacing of the convolutions l6, and the rate of their movement axially of the rolls, can be Varied by increasing o decreasing the skew of the rolls. Since the manner in which the axes of the rolls may be skewed is not part of the present invention and since there is one, or more, well-known methods of skewing the axes of the rolls, further illustration and description of this mechanism are unnecessary.

In carrying out my invention, I produce a controlled high-frequency electric field between the electrodes of an electrostatic circuit, and I cause the'ithread on the thread-storing and advancing device to move, in a controlledma-nner, through saidifield. Also, I so arrange the electrodes asto excludejfthe thread-storing and advancing device from'i-the high-frequency. electric field.

{The high frequency electric field is createdbetween an outer electrode 28 and an inner electrode 30,".f'said electrodes being connected by means of wires 26 to the control device of a conventional electrostatic circuit not shown. The outer elec Mode 28 is preferably arcuatein form so as to encompass a major portion ofthe circumference o'f'the thread-advancing device, and the inner electrode30-is in the form ofsan annulus which encloses the central fixed roll I8. The inner electrode 30 is provided with radial, generally T-shaped, extensions 32,33, 34,35, 36,31 and 38 which are-disposed between the rolls 11, asbest shownin Fig.3. Also, as shown-inthis figure,.the extensions, 33,34, 35,36, 31 and 38 are circumscribed by a yarn circumscribing the rolls II. By this arrangement, theheads 39 of the extensions 32, 33, 34, 35, 36, 31sand 38 areinjjuxtaposition. with corresponding portions of the outer electrode 28, so :that a high-frequency electric field is created therebetween. Again referring to Fig. 3, it will be seen that, as the yarn-moves through the spaces '40 between adjacent rolls, it will pass between the electrode 28 and the corresponding, juxtaposed, electrode extensions 32 to 38 orthrough thehigh-frequency electric fields created between said electrodes.

In the drawings, I have shown seven extensions32, 33, 34, 35, 36,31 and 38, so as to create a high-frequency field across the spaces 40 which intervene between all but two of the rolls n, and I have shown the electrodes as coextensive, longitudinally considered, with therolls IT. However, it'will' be understood that-the electrodes 'may be-made short enough tocover any desired fraction of the length "of the rolls, that they may also be madeto cover any desiredfraction of the circumference of the thread-advancing device, andthat any desired number of extensions 32 to '38 may be used. 'Forexample, if it :is desired to confine the heating to one portion or another of the thread on the rolls, the electrode 28 and the extensions 32 to 38 can be so arranged to create a'high-frequency fieldina selected limited location. Likewise, if it is desired to subjectxthe thread to the heatingaction of a high-frequency fieldonly while it is passing from 1one or'more given rolls onto adjacent rolls, only the corresponding extensions of the inner electrode 3.0

will be used, and the other extensions will be omitted or deenergized, thus limiting the-highfrequency 'electricafield to any given segment of the thread-storing and advancing device.

In addition to controllingthe location, extent and intensity of the high-frequency field in the manner above set forth, the drying operation can be further controlled by varying the spacing of the convolutions [6 of the helix and by regulating rolls were exposed to the high-frequency electric field, they will not become overheated. In practice,,I prefertomakethe rolls from a derivative of acrylic acid, such as methyl methacrylate or similar plastic.

It will, o'f course, be appreciated that evaporation of moisture from the yarn absorbs most, if not all, of the heat generated, so that the yarn does not begin to heat sensibly until it has reached the delivery i end 'of the thread-storing .and ;advancingdevice. Likewise;anyasensibleheat which tends to develop in the rolls I1 willalso be, used up in evaporating the liquid intheyarn oruonathe rolls. Thus, by properly timingthe;control-factors above outlined, undesirable heating of the yarn orof the rolls canbe eliminatedor controlled.

.If desired, instead of using va single pair of electrodes 28 and 30, whichare substantially-coextensive, longitudinally :and circumferentially, with the thread-storing 1 and advancing device, I can use a-plurality of separately operable electrodes land I can selectively energizeone or'more of said electrodes.

In certain cases, it is desirable that a thread or othermaterialmaybe washed, orwliquid+treated in the rplBSBHCBOf heat. Thiszisdiagrammatically illustratedin Fig. 4, in whicha seriesof controlled pipes PPare provided for delivering .one ornmore kindsof liquid with which it is desired to treat the thread. In this construction, the thread .will be subjected to the liquid treatment-and to the heating action of the high-frequency electric field'atthe same time.

What I claim is:

:1. The methodofsubjecting a thread to heat, which method includes winding said threadabout a thread storing andadvancing device ,formed of aplurality ofelongated, spaced rolls placing one electrode-of an electrostaticcircuit within'the area circumscribed by said thread but-in registration-with a selected-number-of the spaces which intervene between adjacent rolls, placing the other electrode of'said circuit "outside of saidiarea but in registration with said spaces, energizing said electrodes, and causing said thread :to .move across said spaceand between said electrodes.

2. The method-of subjecting athreadtocontrolled heat, which method includes winding said thread about .a --:thread storing .and advancing device formed of a plurality "ofrspaced, elongated, substantially parallel rolls with said thread circumscribing allof,saidrolls placing a plurality of electrodesconnected .toone side ofan electrostatic circuit within the areacircumscribed by said thread, with said "electrodes in registration with a corresponding numberof the spaces ,intervening between said-rolls, placing corresponding electrodes, which are -:connected to {the "other side of .saidscircuit, outside 10f said area but :in registration with said spaces, energizing :said electrodes, and causingxsaid thread tomoveacross said spaces. I

3. Apparatus for carrying out'themethod disclosed, .said :apparatus including :a j-plurality of spaced, substantially parallel, elongated rolls adapted to have a thread wound about, and circumscribing all of, said rolls, a first electrode connected to one side of an electro-static circuit and positioned inwardly of the outer peripheriesof said rolls but in registration with a selected number of the spaces intervening between ad.- jacent rolls, a second electrode connected to the other side of said circuit and placed outwardly of the peripheries of said rolls but in juxtaposition with the first mentioned electrode, means for causing the thread to move across said space and between said electrodes, and means for energizing said electrodes.

4. Apparatus for carrying out the method disclosed, said apparatus including a plurality of elongated, spaced, substantially parallel rolls adapted to have a thread wound thereon with said thread circumscribing all of said rolls, a

plurality of electrodes connected to one side of I an electrostatic circuit and placed inwardly of said thread but in registration with selected spaces between said rolls, an electrode placed outwardly of said thread and arranged to register with said electrodes, means for energizing said electrodes, and means for causing said thread to move across said spaces,

5. The combination with a thread storing advancing device formed of a plurality of spaced, elongated, substantially parallel rolls, and including means for causing thread wound about said device to move in a spiral path, transversely of said rolls and axially of said device, of an electrode connected to one side of an electrostatic circuit and located inwardly of a line which encompasses all of said rolls, but in registration with a. selected space intervening between said rolls, and an electrode connected to the other side of said circuit and located outwardly of said line but in registration with said space.

HARRY ASDOUR KULJIAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,531,343 Naite Mar. 31, 1925 1,568,686 Neidich Jan. 5, 1926 2,002,996 Hoefinghoii et a1. May 28, 1935 2,129,273 Hartman et al Sept. 6, 1938 2,281,406 Bergman Apr. 28, 1942 2,291,807 Hart Aug. 4, 1942 2,360,108 Christie Oct. 10, 1944 2,370,624 Gillespie Mar. 6, 1945 2,421,334 Kline et a1. May 27, 1947 2,459,623 Cohoe et a1 Jan. 18, 1949 FOREIGN PATENTS Number Country Date 518,691 Great Britain Mar. 5, 1940 

